summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/base/syscore.c
blob: 8d98a329f6ea63a2daf179bb3f15e5307c6a0d13 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
/*
 *  syscore.c - Execution of system core operations.
 *
 *  Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
 *
 *  This file is released under the GPLv2.
 */

#include <linux/syscore_ops.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/suspend.h>
#include <trace/events/power.h>

static LIST_HEAD(syscore_ops_list);
static DEFINE_MUTEX(syscore_ops_lock);

/**
 * register_syscore_ops - Register a set of system core operations.
 * @ops: System core operations to register.
 */
void register_syscore_ops(struct syscore_ops *ops)
{
	mutex_lock(&syscore_ops_lock);
	list_add_tail(&ops->node, &syscore_ops_list);
	mutex_unlock(&syscore_ops_lock);
}
EXPORT_SYMBOL_GPL(register_syscore_ops);

/**
 * unregister_syscore_ops - Unregister a set of system core operations.
 * @ops: System core operations to unregister.
 */
void unregister_syscore_ops(struct syscore_ops *ops)
{
	mutex_lock(&syscore_ops_lock);
	list_del(&ops->node);
	mutex_unlock(&syscore_ops_lock);
}
EXPORT_SYMBOL_GPL(unregister_syscore_ops);

#ifdef CONFIG_PM_SLEEP
/**
 * syscore_suspend - Execute all the registered system core suspend callbacks.
 *
 * This function is executed with one CPU on-line and disabled interrupts.
 */
int syscore_suspend(void)
{
	struct syscore_ops *ops;
	int ret = 0;

	trace_suspend_resume(TPS("syscore_suspend"), 0, true);
	pr_debug("Checking wakeup interrupts\n");

	/* Return error code if there are any wakeup interrupts pending. */
	if (pm_wakeup_pending())
		return -EBUSY;

	WARN_ONCE(!irqs_disabled(),
		"Interrupts enabled before system core suspend.\n");

	list_for_each_entry_reverse(ops, &syscore_ops_list, node)
		if (ops->suspend) {
			if (initcall_debug)
				pr_info("PM: Calling %pF\n", ops->suspend);
			ret = ops->suspend();
			if (ret)
				goto err_out;
			WARN_ONCE(!irqs_disabled(),
				"Interrupts enabled after %pF\n", ops->suspend);
		}

	trace_suspend_resume(TPS("syscore_suspend"), 0, false);
	return 0;

 err_out:
	pr_err("PM: System core suspend callback %pF failed.\n", ops->suspend);

	list_for_each_entry_continue(ops, &syscore_ops_list, node)
		if (ops->resume)
			ops->resume();

	return ret;
}
EXPORT_SYMBOL_GPL(syscore_suspend);

/**
 * syscore_resume - Execute all the registered system core resume callbacks.
 *
 * This function is executed with one CPU on-line and disabled interrupts.
 */
void syscore_resume(void)
{
	struct syscore_ops *ops;

	trace_suspend_resume(TPS("syscore_resume"), 0, true);
	WARN_ONCE(!irqs_disabled(),
		"Interrupts enabled before system core resume.\n");

	list_for_each_entry(ops, &syscore_ops_list, node)
		if (ops->resume) {
			if (initcall_debug)
				pr_info("PM: Calling %pF\n", ops->resume);
			ops->resume();
			WARN_ONCE(!irqs_disabled(),
				"Interrupts enabled after %pF\n", ops->resume);
		}
	trace_suspend_resume(TPS("syscore_resume"), 0, false);
}
EXPORT_SYMBOL_GPL(syscore_resume);
#endif /* CONFIG_PM_SLEEP */

/**
 * syscore_shutdown - Execute all the registered system core shutdown callbacks.
 */
void syscore_shutdown(void)
{
	struct syscore_ops *ops;

	mutex_lock(&syscore_ops_lock);

	list_for_each_entry_reverse(ops, &syscore_ops_list, node)
		if (ops->shutdown) {
			if (initcall_debug)
				pr_info("PM: Calling %pF\n", ops->shutdown);
			ops->shutdown();
		}

	mutex_unlock(&syscore_ops_lock);
}